diff --git a/tools/docker/test/ubuntu-18.10/dotnet.Dockerfile b/tools/docker/test/ubuntu-18.10/dotnet.Dockerfile
index 6ebedb4c2c..fa1ff4ea2a 100644
--- a/tools/docker/test/ubuntu-18.10/dotnet.Dockerfile
+++ b/tools/docker/test/ubuntu-18.10/dotnet.Dockerfile
@@ -8,7 +8,7 @@ RUN apt-get update -qq \
 # Dotnet install
 RUN apt-get update -qq \
 && apt-get install -yq wget apt-transport-https \
-&& wget -q https://packages.microsoft.com/config/ubuntu/18.10/packages-microsoft-prod.deb \
+&& wget -q https://packages.microsoft.com/config/ubuntu/18.04/packages-microsoft-prod.deb \
 && dpkg -i packages-microsoft-prod.deb \
 && apt-get update -qq \
 && apt-get install -yq dotnet-sdk-2.1 \
diff --git a/tools/docker/ubuntu-18.10.Dockerfile b/tools/docker/ubuntu-18.10.Dockerfile
index c0499e1a4e..b7f7825cf6 100644
--- a/tools/docker/ubuntu-18.10.Dockerfile
+++ b/tools/docker/ubuntu-18.10.Dockerfile
@@ -33,7 +33,7 @@ RUN apt-get update -qq \
 # Dotnet Install
 RUN apt-get update -qq \
 && apt-get install -yq apt-transport-https \
-&& wget -q https://packages.microsoft.com/config/ubuntu/18.10/packages-microsoft-prod.deb \
+&& wget -q https://packages.microsoft.com/config/ubuntu/18.04/packages-microsoft-prod.deb \
 && dpkg -i packages-microsoft-prod.deb \
 && apt-get update -qq \
 && apt-get install -yq dotnet-sdk-2.1 \